Socioeconomic inequalities in attending the mass screening for breast cancer in the south of the Netherlands--associations with stage at diagnosis and survival

Impact of organized and opportunistic screening on excess mortality and on social inequalities in breast cancer survival

In most developed countries, both organized screening (OrgS) and opportunistic screening (OppS) coexist. The literature has extensively covered the impact of organized screening on women's survival after breast cancer. However, the impact of opportunistic screening has been less frequently described due to the challenge of identifying the target population. The aim of this study was to describe the net survival and excess mortality hazard (EMH) in each screening group (OrgS, OppS, or No screening) and to determine whether there is an identical social gradient in each groups. Three data sources (cancer registry, screening coordination centers, and National Health Data System [NHDS]) were used to identify the three screening groups. The European Deprivation Index (EDI) defined the level of deprivation. We modeled excess breast cancer mortality hazard and net survival using penalized flexible models. We observed a higher EMH for "No screening" women compared with the other two groups, regardless of level of deprivation and age at diagnosis. A social gradient appeared for each group at different follow-up times and particularly between 2 and 3 years of follow-up for "OrgS" and "OppS" women. Net survival was higher for "OrgS" women than "OppS" women, especially for the oldest women, and regardless of the deprivation level. This study provides new evidence of the impact of OrgS on net survival and excess mortality hazard after breast cancer, compared with opportunistic screening or no screening, and tends to show that OrgS attenuates the social gradient effect.

Linguistic difference in the effect of organized programs on socioeconomic inequalities in breast cancer screening: ecological study in Switzerland

OBJECTIVE

The objective of this study is to examine how the effect of organized mammography screening programs on breast cancer screening participation differ between socioeconomic strata and how this relationship may be modified by the context of linguistic differences. Switzerland, marked by its diverse linguistic landscape, reflects cultural variations alongside differences in public health strategies. The goal of this study was to assess potential socioeconomic differences in regional mammography screening programs effectiveness to improve breast cancer screening participation.

METHODS

Data on 14 173 women in the regionally adapted breast cancer screening age range was drawn from five cross-sectional waves of the nationally representative Swiss Health Interview Survey (1997-2017). Socioeconomic indicators included education, household income, and employment status. Poisson regression was used to estimate the adjusted prevalence ratios of up-to-date (last 2 years) mammography uptake. Inequality was assessed using relative index of inequality and the slope index of inequality.

RESULTS

Organized screening programs were generally effective and increased up-to-date mammography uptake by close to 20 percentage points in both regions. While in the Latin cantons, screening programs had no impact on socioeconomic inequalities in screening, it reduced inequalities for women with lower education in the German cantons. This modification effect of screening programs was not seen for income and employment-related inequalities and did not differ across linguistic regions.

CONCLUSIONS

Public health agencies should consider the different cultural reception of programs as addressing these differences could help ensure that breast cancer screening initiatives are not only effective, but also culturally equitable across different socioeconomic groups.

Breast cancer patients enrolled in the Swiss mammography screening program "donna" demonstrate prolonged survival

STUDY GOAL

We compared the survival rates of women with breast cancer (BC) detected within versus outside the mammography screening program (MSP) "donna".

METHODS

We merged data from the MSP with the data from corresponding cancer registries to categorize BC cases as within MSP (screen-detected and interval carcinomas) and outside the MSP. We analyzed the tumor stage distribution, tumor characteristics and the survival of the women. We further estimated hazard ratios using Cox-regressions to account for different characteristics between groups and corrected the survival rates for lead-time bias.

RESULTS

We identified 1057 invasive (ICD-10: C50) and in-situ (D05) BC cases within the MSP and 1501 outside the MSP between 2010 and 2019 in the Swiss cantons of St. Gallen and Grisons. BC within the MSP had a higher share of stage I carcinoma (46.5% vs. 33.0%; p < 0.01), a smaller (mean) tumor size (19.1 mm vs. 24.9 mm, p < 0.01), and fewer recurrences and metastases in the follow-up period (6.7% vs. 15.6%, p < 0.01). The 10-year survival rates were 91.4% for women within and 72.1% for women outside the MSP (p < 0.05). Survival difference persisted but decreased when women within the same tumor stage were compared. Lead-time corrected hazard ratios for the MSP accounted for age, tumor size and Ki-67 proliferation index were 0.550 (95% CI 0.389, 0.778; p < 0.01) for overall survival and 0.469 (95% CI 0.294, 0.749; p < 0.01) for BC related survival.

CONCLUSION

Women participating in the "donna" MSP had a significantly higher overall and BC related survival rate than women outside the program. Detection of BC at an earlier tumor stage only partially explains the observed differences.

Socioeconomic Deprivation and Invasive Breast Cancer Incidence by Stage at Diagnosis: A Possible Explanation to the Breast Cancer Social Paradox

In this study, we assessed the influence of area-based socioeconomic deprivation on the incidence of invasive breast cancer (BC) in France, according to stage at diagnosis. All women from six mainland French departments, aged 15+ years, and diagnosed with a primary invasive breast carcinoma between 2008 and 2015 were included (n = 33,298). Area-based socioeconomic deprivation was determined using the French version of the European Deprivation Index. Age-standardized incidence rates (ASIR) by socioeconomic deprivation and stage at diagnosis were compared estimating incidence rate ratios (IRRs) adjusted for age at diagnosis and rurality of residence. Compared to the most affluent areas, significantly lower IRRs were found in the most deprived areas for all-stages (0.85, 95% CI 0.81-0.89), stage I (0.77, 95% CI 0.72-0.82), and stage II (0.84, 95% CI 0.78-0.90). On the contrary, for stages III-IV, significantly higher IRRs (1.18, 95% CI 1.08-1.29) were found in the most deprived areas. These findings provide a possible explanation to similar or higher mortality rates, despite overall lower incidence rates, observed in women living in more deprived areas when compared to their affluent counterparts. Socioeconomic inequalities in access to healthcare services, including screening, could be plausible explanations for this phenomenon, underlying the need for further research.

Factors influencing breast cancer screening practices among women worldwide: a systematic review of observational and qualitative studies

BACKGROUND

The variation in breast cancer incidence rates across different regions may reflect disparities in breast cancer screening (BCS) practices. Understanding the factors associated with these screening behaviors is crucial for identifying modifiable elements amenable to intervention. This systematic review aims to identify common factors influencing BCS behaviors among women globally.

METHODS

Relevant papers were sourced from PubMed, Scopus, Embase, and Google Scholar. The included studies were published in English in peer-reviewed journals from January 2000 to March 2023 and investigated factors associated with BCS behaviors.

RESULTS

From an initial pool of 625 articles, 34 studies (comprising 29 observational and 5 qualitative studies) with 36,043 participants were included. Factors influencing BCS behaviors were categorized into nine groups: socio-demographic factors, health status history, knowledge, perceptions, cultural factors, cues to action, motivation, self-efficacy, and social support. The quality appraisal scores of the studies ranged from average to high.

CONCLUSIONS

This systematic review highlights factors pivotal for policy-making at various levels of breast cancer prevention and assists health promotion professionals in designing more effective interventions to enhance BCS practices among women.

Knowledge, attitudes, and practices related to breast cancer screening among female Jordanian university employees: A cross-sectional study

INTRODUCTION

To improve participation in breast screening programs, the level of knowledge about BC, attitudes, and practices of women in different sections of society must be understood. This study aimed to measure the level of knowledge of BC risk factors, signs and symptoms and determine current mammography practices among female employees at Jordanian universities.

METHODS

A cross-sectional descriptive study was conducted on female employees at Jordanian government universities. Data was collected using a structured questionnaire that included: sociodemographic characteristics, knowledge of BC risk factors, knowledge of BC symptoms and knowledge, attitude and practice of mammography as an early detection method.

RESULTS

A total of 362 participants completed the questionnaire. Overall, 174 scored ≥50% correct answers regarding BC risk factors, while 231 scored ≥50% correct answers regarding BC signs and symptoms. Half of the participants (n = 184, 50.8%) understood mammography to be an early BC detection method. Among those participants, 95 (51.6%) were eligible for screening and 39 (21.2%) had had a previous mammogram. The main reason for not engaging in mammography was the absence of BC signs and symptoms (37.2%). Profession, educational level and family history of BC were associated with increased knowledge of BC risk factors, signs and symptoms (p = 0.01). Lecturers in medical faculties exhibited the highest level of knowledge about mammography compared to participants in other professions (p = 0.02).

CONCLUSION

Only 79 participants had good to excellent knowledge about BC. Participants' profession was the major indicator for awareness of BC and mammography as an early detection method.

IMPLICATIONS FOR PRACTICE

The findings of this study reinforce the importance of providing BC educational programs for university employees in Jordan to increase awareness of BC and mammography.

Attendance characteristics of the breast and colorectal cancer screening programmes in a highly urbanised region of the Netherlands: a retrospective observational study

OBJECTIVES

Throughout Europe, many countries offer population-based cancer screening programmes (CSPs). In the Netherlands, two implemented CSPs are targeting people of 50 years and older, aiming at breast cancer (BC) and colorectal cancer (CRC). In order for a CSP to be (cost-)effective, high participation rates and outreach to the populations at risk are essential. People living in highly urbanised areas and big cities are known to participate less in CSPs. The aim of this study was to gain further insight into the participation patterns of a screening-eligible population of 50 years and over, living in a highly urbanised region, over a longer time period.

DESIGN

A retrospective observational study.

SETTING

Participation data of the regional screening organisation, linked to the cancer incidence data derived from the Netherlands Cancer Registry, concerning the city of The Hague, between 2005 and 2019. Attendance groups were defined as attenders (attending >50% of the invitations) and non-attenders (attending ≤50% of the invitations), and were mutually compared.

RESULTS

The databases contained 106 377 unique individuals on the BC screening programme (SP) and 73 669 on the CRC-SP. Non-attendance at both CSPs was associated with living in a lower socioeconomic status (SES) neighbourhood and as a counter effect, also associated with a more unfavourable, relatively late-stage, tumour diagnosis. When combining the results of the two CSPs, our results imply high screening adherence over time. Women who did not participate in both CSPs were older, and more often lived in neighbourhoods with a lower SES score.

CONCLUSIONS

Since low screening uptake is one of the factors that contribute to increasing inequalities in cancer survival, future outreach strategies should be focused on engaging specific non-attending subgroups.

Screening behaviours, demographics, and stage at diagnosis in the publicly funded Ontario Breast Screening Program

PURPOSE

The Ontario Breast Screening Program (OBSP) offers free screening mammograms every 2 years, to women aged 50-74. Study objectives were to determine demographic characteristics associated with the adherence to OBSP and if women screened in the OBSP have a lower stage at diagnosis than non-screened eligible women.

METHODS

We used the Ontario cancer registry (OCR) to identify 48,927 women, aged 51-74 years, diagnosed with breast cancer between 2010 and 2017. These women were assigned as having undergone adherent screening (N = 26,108), non-adherent screening (N = 6546) or not-screened (N = 16,273) in the OBSP. We used multinomial logistic regression to investigate the demographic characteristics associated with screening behaviour, as well as the association between screening status and stage at diagnosis.

RESULTS

Among women with breast cancer, those living in rural areas (versus the largest urban areas) had a lower odds of not being screened (odds ratio [OR] 0.73, 95% confidence interval [CI] 0.68, 0.78). Women in low-income (versus high-income) communities were more likely not to be screened (OR 1.42, 95% CI 1.33, 1.51). When stratified, the association between income and screening status only held in urban areas. Non-screened women were more likely to be diagnosed with stage II (OR 1.91, 95% CI 1.82, 2.01), III (OR 2.96, 95% CI 2.76, 3.17), or IV (OR 8.96, 95% CI 7.94, 10.12) disease compared to stage I and were less likely to be diagnosed with ductal carcinoma in situ (DCIS) (OR 0.91, 95% CI 0.84-0.98).

CONCLUSIONS

This study suggests that targeting OBSP recruitment efforts to lower income urban communities could increase screening rates. OBSP adherent women were more likely to be diagnosed with earlier stage disease, supporting the value of this initiative and those like it.

Irregular screening participation increases advanced stage breast cancer at diagnosis: A population-based study

OBJECTIVE

To evaluate the effect of irregular screening behaviour on the risk of advanced stage breast cancer at diagnosis in Flanders.

METHODS

All women aged 50-69 who were invited to the organized breast cancer screening and diagnosed with breast cancer before age 72 from 2001 to 2018 were included. All prevalent screen and interval cancers within 2 years of a prevalent screen were excluded. Screening behaviour was categorized based on the number of invitations and performed screenings. Four groups were defined: regular, irregular, only-once, and never attenders. Advanced stage cancer was defined as a stage III + breast cancer. The association between screening regularity and breast cancer stage at diagnosis was evaluated in multivariable logistic regression models, taking age of diagnosis and socio-economic status into account.

RESULTS

In total 13.5% of the 38,005 breast cancer cases were diagnosed at the advanced stage. Compared to the regular attenders, the risk of advanced stage breast cancer for the irregular attenders, women who participated only-once, and never attenders was significantly higher with OR_adjusted:1.17 (95%CI:1.06-1.29) and OR_adjusted:2.18 (95%CI:1.94-2.45), and OR_adjusted:5.95 (95%CI:5.33-6.65), respectively.

CONCLUSIONS

In our study, never attenders were nearly six times more likely to be diagnosed with advanced stage breast cancer than regular attenders, which was much higher than the estimates published thus far. An explanation for this is that the ever screened women is a heterogeneous group regarding the participation profiles which also includes irregular and only-once attenders. The benefit of regular screening should be informed to all women invited for screening.

Socioeconomic differences in participation and diagnostic yield within the Dutch national colorectal cancer screening programme with faecal immunochemical testing

Background

CRC mortality rates are higher for individuals with a lower socioeconomic status (SES). Screening could influence health inequalities. We therefore aimed to investigate SES differences in participation and diagnostic yield of FIT screening.

Methods

All invitees in 2014 and 2015 in the Dutch national CRC screening programme were included in the analyses. We used area SES as a measure for SES and divided invitees into quintiles, with Quintile 1 being the highest SES. Logistic regression analysis was used to compare the participation rate, positivity rate, colonoscopy uptake, positive predictive value (PPV) and detection rate across the SES groups.

Results

Participation to FIT screening was significantly lower for Quintile 5 (67.0%) compared to the other Quintiles (73.0% to 75.1%; adjusted OR quintile 5 versus quintile 1: 0.73, 95%CI: 0.72–0.74), as well as colonoscopy uptake after a positive FIT (adjusted OR 0.73, 95%CI: 0.69–0.77). The detection rate per FIT participant for advanced neoplasia gradually increased from 3.3% in Quintile 1 to 4.0% in Quintile 5 (adjusted OR 1.20%, 95%CI 1.16–1.24). As a result of lower participation, the yield per invitee was similar for Quintile 5 (2.04%) and Quintile 1 (2.00%), both being lower than Quintiles 2 to 4 (2.20%-2.28%).

Conclusions

Screening has the potential to reduce health inequalities in CRC mortality, because of a higher detection in participants with a lower SES. However, in the Dutch screening programme, this is currently offset by the lower participation in this group.

Revisiting the Effects of Organized Mammography Programs on Inequalities in Breast Screening Uptake: A Multilevel Analysis of Nationwide Data From 1997 to 2017

This study revisits the effects of mammography screening programs on inequalities in breast screening uptake in Switzerland. The progressive introduction of regional mammography programs by 12 out of the 26 Swiss cantons (regions) since 1999 offers an opportunity to perform an ecological quasi-experimental study. We examine absolute income and marital status inequalities in mammography uptake, and whether the cantons' implementation of mammography programs moderate these inequalities, as previous research has devoted little attention to this. We use five waves of the Swiss Health Interview Survey covering the 1997-2017 period and comprising data on 14,267 women aged 50-70. Both up-to-date and ever-screening outcomes are analyzed with multilevel models which assess the mammography programs' within-canton effect. Findings show that higher income women and married women (compared to unmarried women) had significantly higher mammography uptake probabilities. Mammography programs did not moderate absolute income differences in up-to-date screening; however, they were associated with smaller absolute income differences in ever-screening uptake. Mammography programs related to higher screening uptake for married women, more than for unmarried women. In conclusion, we showed absolute income inequalities in mammography uptake which were not revealed by previous studies using relative inequality measures. Mammography programs may have contributed to reducing income inequalities in ever-screening, yet this was not observed for up-to-date screening. This study has implication for preventive health interventions-e.g., cancer screening promotion should pay attention to women's marital status since screening programs may widen the screening gap between married and unmarried women.

Socio-economic Inequality of Utilization of Cancer Testing in Europe: A Cross-Sectional Study

There are currently screening programmes for breast, cervical and colorectal cancer in many European countries. However, the uptake of cancer screening in general may vary within and between countries. The aim of this study is to assess the inequalities in testing utilization by socio-economic status and whether the amount of inequality varies across European regions. We conducted an analysis based on cross-sectional data from the second wave of the European Health Interview Survey from 2013 to 2015. We analysed the use of breast, cervical, and colorectal cancer testing by socio-economic position (household income, educational level and employment status), socio-demographic factors, self-perceived health and smoking behaviour, by using multinomial logistic models, and inequality measurement based on the Slope index of inequality (SII) and Relative index of inequality (RII). The results show that the utilization of mammography (Odds Ratio (OR) = 0.55, 95% confidence interval (95%CI):0.50–0.61), cervical smear tests (OR = 0.60, 95%CI:0.56–0.65) and colorectal testing (OR = 0.82, 95%CI:0.78–0.86) was overall less likely among individuals within a low household income compared to a high household income. Also, individuals with a non-EU country of birth, low educational level and being unemployed (or retired) were overall less likely to be tested. The income-based inequality in breast (SII = 0.191;RII = 1.260) and colorectal testing utilization (SII = 0.161;RII = 1.487) was the greatest in Southern Europe. For cervical smears, this inequality was greatest in Eastern Europe (SII = 0.122;RII = 1.195). We concluded that there is considerable inequality in the use of cancer tests in Europe, with inequalities associated with household income, educational level, employment status, and country of birth.

Factors associated with attendance at screening for breast cancer: a systematic review and meta-analysis

OBJECTIVE

Attendance at population-based breast cancer (mammographic) screening varies. This comprehensive systematic review and meta-analysis assesses all identified patient-level factors associated with routine population breast screening attendance.

DESIGN

CINAHL, Cochrane Library, Embase, Medline, OVID, PsycINFO and Web of Science were searched for studies of any design, published January 1987-June 2019, and reporting attendance in relation to at least one patient-level factor.

DATA SYNTHESIS

Independent reviewers performed screening, data extraction and quality appraisal. OR and 95% CIs were calculated for attendance for each factor and random-effects meta-analysis was undertaken where possible.

RESULTS

Of 19 776 studies, 335 were assessed at full text and 66 studies (n=22 150 922) were included. Risk of bias was generally low. In meta-analysis, increased attendance was associated with higher socioeconomic status (SES) (n=11 studies; OR 1.45, 95% CI: 1.20 to 1.75); higher income (n=5 studies; OR 1.96, 95% CI: 1.68 to 2.29); home ownership (n=3 studies; OR 2.16, 95% CI: 2.08 to 2.23); being non-immigrant (n=7 studies; OR 2.23, 95% CI: 2.00 to 2.48); being married/cohabiting (n=7 studies; OR 1.86, 95% CI: 1.58 to 2.19) and medium (vs low) level of education (n=6 studies; OR 1.24, 95% CI: 1.09 to 1.41). Women with previous false-positive results were less likely to reattend (n=6 studies; OR 0.77, 95% CI: 0.68 to 0.88). There were no differences by age group or by rural versus urban residence.

CONCLUSIONS

Attendance was lower in women with lower SES, those who were immigrants, non-homeowners and those with previous false-positive results. Variations in service delivery, screening programmes and study populations may influence findings. Our findings are of univariable associations. Underlying causes of lower uptake such as practical, physical, psychological or financial barriers should be investigated.

TRIAL REGISTRATION NUMBER

CRD42016051597.

Population-based mammography screening attendance in Sweden 2017-2018: A cross-sectional register study to assess the impact of sociodemographic factors

Sweden has a population-based mammography screening programme for women aged 40–74. The objective of this study was to examine the association between mammography screening attendance and sociodemographic factors in 15 of Sweden's 21 health care regions. Register-based information was collected on all mammography screening invitations and attendance during 2017 and 2018, and linked to individual-level sociodemographic data from Statistics Sweden. Odds ratios (ORs) and 95% confidence intervals (CIs) for attendance were computed by sociodemographic factor. The study sample included 1.5 million women, aged 40–75, with an overall screening attendance of 81.3%. The lowest odds of attending were found for women living without a partner (OR = 0.52, 95% CI: 0.52–0.53), low-income women (OR = 0.57, 95% CI: 0.56–0.57), and non-Nordic women born in Europe (OR = 0.60, 95% CI: 0.59–0.61). Other groups with lower odds of attending were women whose main source of income was social assistance or benefits (OR = 0.62, 95% CI: 0.62–0.63), those not owning their home (OR = 0.66, 95% CI: 0.66–0.67), and those with low level of education (OR = 0.72, 95% CI: 0.71–0.73). Having multiple of these sociodemographic characteristics further lowered the odds of attending. Although overall mammography screening attendance in Sweden is high, sociodemographic inequalities exist, and efforts should be made to address these. Particular attention should be given to low-income women who live without a partner.

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Mammography screening attendance in Sweden was 81% in 2017–2018.

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Sociodemographic inequalities were found for screening attendance.

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Having multiple low attendance risk factors further decreased the odds of attending.

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Lowest attendance among low-income women who live without a partner.

Small-area analysis on socioeconomic inequalities in cancer survival for 25 cancer sites in Germany

Socioeconomic inequalities in cancer survival have been reported in various countries but it is uncertain to what extent they persist in countries with relatively comprehensive health insurance coverage such as Germany. We investigated the association between area-based socioeconomic deprivation on municipality level and cancer survival for 25 cancer sites in Germany. We used data from seven population-based cancer registries (covering 32 million inhabitants). Patients diagnosed in 1998 to 2014 with one of 25 most common cancer sites were included. Area-based socioeconomic deprivation was assessed using the categorized German Index of Multiple Deprivation (GIMD) on municipality level. We estimated 3-month, 1-year, 5-year and 5-year conditional on 1-year age-standardized relative survival using period approach for 2012 to 2014. Trend analyses were conducted for periods between 2003-2005 and 2012-2014. Model-based period analysis was used to calculate relative excess risks (RER) adjusted for age and stage. In total, 2 333 547 cases were included. For all cancers combined, 5-year survival rates by GIMD quintile were 61.6% in Q1 (least deprived), 61.2% in Q2, 60.4% in Q3, 59.9% in Q4 and 59.0% in Q5 (most deprived). For most cancer sites, the most deprived quintile had lower 5-year survival compared to the least deprived quintile even after adjusting for stage (all cancer sites combined, RER 1.16, 95% confidence interval 1.14-1.19). For some cancer sites, this association was stronger during short-term follow-up. Trend analyses showed improved survival from earlier to recent periods but persisting deprivation differences. The underlying reasons for these persisting survival inequalities and strategies to overcome them should be further investigated.

Sociodemographic Factors Associated With Rapid Relapse in Triple-Negative Breast Cancer: A Multi-Institution Study

BACKGROUND

Triple-negative breast cancer (TNBC) accounts for disproportionately poor outcomes in breast cancer, driven by a subset of rapid-relapse TNBC (rrTNBC) with marked chemoresistance, rapid metastatic spread, and poor survival. Our objective was to evaluate clinicopathologic and sociodemographic features associated with rrTNBC.

METHODS

We included patients diagnosed with stage I-III TNBC in 1996 through 2012 who received chemotherapy at 1 of 10 academic cancer centers. rrTNBC was defined as a distant metastatic recurrence event or death ≤24 months after diagnosis. Features associated with rrTNBC were included in a multivariable logistic model upon which backward elimination was performed with a P<.10 criterion, with a final multivariable model applied to training (70%) and independent validation (30%) cohorts.

RESULTS

Among all patients with breast cancer treated at these centers, 3,016 fit the inclusion criteria. Training cohort (n=2,112) bivariable analyses identified disease stage, insurance type, age, body mass index, race, and income as being associated with rrTNBC (P<.10). In the final multivariable model, rrTNBC was significantly associated with higher disease stage (adjusted odds ratio for stage III vs I, 16.0; 95% CI, 9.8-26.2; P<.0001), Medicaid/indigent insurance, lower income (by 2000 US Census tract), and younger age at diagnosis. Model performance was consistent between the training and validation cohorts. In sensitivity analyses, insurance type, low income, and young age were associated with rrTNBC among patients with stage I/II but not stage III disease. When comparing rrTNBC versus late relapse (>24 months), we found that insurance type and young age remained significant.

CONCLUSIONS

Timing of relapse in TNBC is associated with stage of disease and distinct sociodemographic features, including insurance type, income, and age at diagnosis.

Factors Explaining Socio-Economic Inequalities in Cancer Survival: A Systematic Review

BACKGROUND

There is strong and well-documented evidence that socio-economic inequality in cancer survival exists within and between countries, but the underlying causes of these differences are not well understood.

METHODS

We systematically searched the Ovid Medline, EMBASE, and CINAHL databases up to 31 May 2020. Observational studies exploring pathways by which socio-economic position (SEP) might causally influence cancer survival were included.

RESULTS

We found 74 eligible articles published between 2005 and 2020. Cancer stage, other tumor characteristics, health-related lifestyle behaviors, co-morbidities and treatment were reported as key contributing factors, although the potential mediating effect of these factors varied across cancer sites. For common cancers such as breast and prostate cancer, stage of disease was generally cited as the primary explanatory factor, while co-morbid conditions and treatment were also reported to contribute to lower survival for more disadvantaged cases. In contrast, for colorectal cancer, most studies found that stage did not explain the observed differences in survival by SEP. For lung cancer, inequalities in survival appear to be partly explained by receipt of treatment and co-morbidities.

CONCLUSIONS

Most studies compared regression models with and without adjusting for potential mediators; this method has several limitations in the presence of multiple mediators that could result in biased estimates of mediating effects and invalid conclusions. It is therefore essential that future studies apply modern methods of causal mediation analysis to accurately estimate the contribution of potential explanatory factors for these inequalities, which may translate into effective interventions to improve survival for disadvantaged cancer patients.

Factors associated with being diagnosed with high severity of breast cancer: a population-based study in Queensland, Australia

PURPOSE

This study explores factors that are associated with the severity of breast cancer (BC) at diagnosis.

METHODS

Interviews were conducted among women (n = 3326) aged 20-79 diagnosed with BC between 2011 and 2013 in Queensland, Australia. High-severity cancers were defined as either Stage II-IV, Grade 3, or having negative hormone receptors at diagnosis. Logistic regression models were used to estimate odds ratios (ORs) of high severity BC for variables relating to screening, lifestyle, reproductive habits, family history, socioeconomic status, and area disadvantage.

RESULTS

Symptom-detected women had greater odds (OR 3.38, 2.86-4.00) of being diagnosed with high-severity cancer than screen-detected women. Women who did not have regular mammograms had greater odds (OR 1.78, 1.40-2.28) of being diagnosed with high-severity cancer than those who had mammograms biennially. This trend was significant in both screen-detected and symptom-detected women. Screen-detected women who were non-smokers (OR 1.77, 1.16-2.71), postmenopausal (OR 2.01, 1.42-2.84), or employed (OR 1.46, 1.15-1.85) had greater odds of being diagnosed with high-severity cancer than those who were current smokers, premenopausal, or unemployed. Symptom-detected women being overweight (OR 1.67, 1.31-2.14), postmenopausal (OR 2.01, 1.43-2.82), had hormone replacement therapy (HRT) < 2 years (OR 1.60, 1.02-2.51) had greater odds of being diagnosed with high-severity cancer than those of healthy weight, premenopausal, had HRT > 10 years.

CONCLUSION

Screen-detected women and women who had mammograms biennially had lower odds of being diagnosed with high-severity breast cancer, which highlighted the benefit of regular breast cancer screening. Women in subgroups who are more likely to have more severe cancers should be particularly encouraged to participate in regular mammography screening.

Impact of mammographic screening and advanced cancer definition on the percentage of advanced-stage cancers in a steady-state breast screening programme in the Netherlands

Background

To estimate the percentages of advanced-stage breast cancers (BCs) detected during the course of a steady-state screening programme when using different definitions of advanced BC.

Methods

Data of women aged 49–74 years, diagnosed with BC in 2006–2015, were selected from the Netherlands Cancer Registry and linked to the screening registry. BCs were classified as screen-detected, interval or non-screened. Three definitions of advanced BC were used for comparison: TNM stage (III–IV), NM stage (N+ and/or M+) and T size (invasive tumour ≥15 mm). Analyses were performed assuming a 10% overdiagnosis rate. In sensitivity analyses, this assumption varied from 0 to 30%.

Results

We included 46,734 screen-detected, 17,362 interval and 24,189 non-screened BCs. By TNM stage, 4.9% of screen-detected BCs were advanced, compared with 19.4% and 22.8% of interval and non-screened BCs, respectively (p < 0.001). Applying the other definitions led to higher percentages of advanced BC being detected. Depending on the definition interval, non-screened BCs had a 2–5-times risk of being advanced.

Conclusion

Irrespective of the definition, screen-detected BCs were less frequently in the advanced stage. These findings provide evidence of a stage shift to early detection and support the potential of mammographic screening to reduce treatment-related burdens and the mortality associated with BC.

The Melanoma and Breast Cancer Association: An Overview of their 'Second Primary Cancers' and the Epidemiological, Genetic and Biological correlations

This study reviews the relevant epidemiological studies associating cutaneous melanoma and breast carcinomas and provides an overview of the possible genetic, biological and bias factors that underpin this relationship. Standardised incidence ratio (SIR) for primary cutaneous melanoma after breast carcinoma ranged from 1.16 to 5.13 and ranged from 1.03 to 4.10 for primary breast carcinoma after cutaneous melanoma. Epidemiological studies highlight age, gender and use of radiotherapy and chemotherapy as potential risk factors for second primary cancers (SPCs). Mutations in BRCA2, CDKN2A, CDK4 and BAP1 may partly underlie any SPC association. The impact of socio-cultural factors and surveillance bias may be attributed to the findings of SPC partially or entirely. In conclusion, this study has highlighted the association between breast carcinoma and melanoma and identified various factors for further research and the optimised management of patients with both cancers.

Socioeconomic Inequalities in Uptake of Breast Cancer Screening among Saudi Women: A Cross-Sectional Analysis of a National Survey

Timely and adequate screening for breast cancer could improve health outcomes and reduce health costs. However, the utilization of free breast cancer screening services among Saudi women is very low. This study aims to investigate socioeconomic inequalities in breast cancer screening among Saudi women. The data of this study were extracted from the nationally representative Saudi Health Interview Survey, conducted in 2013; the study included 2786 Saudi women. Multivariate logistic regression, the concentration curve, and the concentration index were used to examine, illustrate, and quantify income- and education-related inequalities in three outcomes: Knowledge about self-breast examination (SBE), clinical breast examination (CBE) received in the last year, and mammography, that has ever been previously carried out. Results showed a marked socioeconomic gradient in breast cancer screening services. The concentration index by income was 0.229 (SBE), 0.171 (CBE), and 0.163 (mammography). The concentration index by education was 0.292 (SBE), 0.149 (CBE), and 0.138 (mammography). Therefore, knowledge about breast cancer screening, and the utilization of screening services, were more concentrated among richer and better-educated women. Poorer and less educated women had less knowledge about self-breast examination, and had considerably less adherence to clinical breast examination and mammography. The findings are helpful for policy makers to devise and implement strategies to promote equity in breast cancer screening among Saudi women.

Determinants of (non-)attendance at the Dutch cancer screening programmes: A systematic review

Objective

The Netherlands host three population-based cancer screening programmes: for cervical, breast, and colorectal cancer. For screening programmes to be effective, high participation rates are essential, but participation in the Netherlands’ programmes is starting to fall below the minimal effective rate. We aimed to produce a systematic overview of the current known determinants of (non-)attendance at the Dutch cancer screening programmes.

Methods

A literature search was conducted in the electronic databases Academic Search Premier, Cochrane Library, Embase, EMCare, PubMed, PsycINFO, Web of Science, and also in grey literature, including all articles published before February 2018. The I-Change model was used to categorize the identified determinants of cancer screening attendance.

Results

In total, 19/1232 identified studies and 6 grey literature reports were included. Fifteen studies reported on predisposing factors. Characteristics such as social economic status, country of birth, and residency were most often reported, and correlate with cancer screening attendance. Thirteen studies addressed information factors. Factors on awareness, motivation, ability, and barriers were less often studied.

Conclusion

Current studies tend to describe the general characteristics of (non-)attendance and (non-)attenders, but rarely provide in depth information on other factors of (non-)participation. The I-Change model proved to be a useful tool in mapping current knowledge on cancer screening attendance and revealed knowledge gaps regarding determinants of (non-)participation in the screening programmes. More research is needed to fully understand determinants of participation, in order to influence and optimize attendance rates over the long term.

The breast cancer paradox: A systematic review of the association between area-level deprivation and breast cancer screening uptake in Europe

Breast cancer rates are lower amongst women from more socio-economically deprived areas. However, their mortality rates are higher. One explanation of this breast cancer paradox is that women from more deprived areas are less likely to attend breast cancer screening programmes. This systematic review is the first to examine this issue in Europe. A systematic review of Embase, Medline and PsychINFO (from 2008 to 2019) was undertaken (PROSPERO registration number: CRD42018083703). Observational studies were included if they were based in Europe, measured breast cancer screening uptake, compared at least two areas, included an area-level measure of socio-economic deprivation and were published in the English language. The Joanna Briggs Institute critical appraisal checklist was used to assess study quality and risk of bias. Thirteen studies from seven different European countries met our inclusion criteria and were included in the review. In ten of the thirteen studies, there was a significant negative association between screening uptake and area-level socio-economic deprivation - with women living in more socio-economically deprived neighbourhoods less likely to attend breast cancer screening. Although universal screening programmes were provided in most studies, there were still strong negative associations between screening uptake and area-level socio-economic deprivation. Future breast cancer screening strategies should acknowledge these challenges, and consider developing targeted interventions in more deprived areas to increase screening participation.

Comorbidity Index as a Predictor of Mortality in Pediatric Patients With Solid Tumors

Purpose: The objective of this study was to determine whether a comorbidity index could be used to predict mortality in pediatric patients with chemotherapy-treated solid tumors. Methods: Pediatric patients who underwent chemotherapy treatment for solid tumors were included, and demographic, clinical, and comorbidity data were obtained from patient electronic records. Results: A total of 196 pediatric patients with embryonic solid tumors were included. Metastatic tumors were the most frequently observed (n = 103, 52.6%). The most common comorbidities encountered for the Charlson comorbidity index (CCI) were cellulitis (n = 24, 12.2%) and acute renal failure (n = 15, 7.7%). For the Pediatric Comorbidity Index (PCI), the most frequent comorbidities were pneumonia and sepsis, with n = 64 (32.7%) for each. We evaluated established the prognostic values for both indexes using Kaplan-Meier curves, finding that the CCI and PCI could predict mortality with p < 0.0001. Conclusion: Using the PCI, we observed 100% survival in patients without comorbidities, 70% survival in patients with a low degree of comorbidity, and 20% survival in patients with a high degree of comorbidity. Greater discrimination of probability of survival could be achieved using degrees of comorbidity on the PCI than using degrees of comorbidity on the CCI. The application of the PCI for assessing the hospitalized pediatric population may be of importance for improving clinical evaluation.

Organised population-based programmes and change in socioeconomic inequalities in mammography screening: A 1992-2012 nationwide quasi-experimental study

Organised mammography screening programmes may reduce socioeconomic inequalities in breast cancer screening, but evidence is contradictory. Switzerland has no national organised mammography screening programme, but regional programmes were progressively introduced since 1999, giving the opportunity to conduct a nationwide quasi-experimental study. We examined the evolution of socioeconomic inequalities in mammography screening in Switzerland and if exposure to regional organised programmes reduced socioeconomic inequalities. Data of 10,927 women aged 50 to 70 years old were collected from the Swiss Health Interview Survey, a nationally representative cross-sectional survey repeated 5 times (1992-2012). Socioeconomic characteristics were assessed using education, income, employment status, and occupational class. Adjusted prevalence ratios of up-to-date mammography screening were estimated with Poisson regressions and weighted for sampling strategy and non-participation bias. In the absence of organised screening programmes (1992-1997), prevalence of mammography screening increased by 23% and was associated with tertiary education and working part time. During the period of progressive introduction of regionally organised programmes (2002-2012), prevalence of mammography screening increased by 19% every 5 years and was associated with exposure to regional programmes and with independent/artisan occupations. Tertiary education and working part time were no longer associated. Exposure to organised programmes did not modify socioeconomic inequalities except for employment status: not employed women benefitted more from organised programmes compared to women working full time. In conclusion, socioeconomic inequalities in mammography screening decreased over time but organised programmes did not greatly modify them, except women not employed whose prevalence passed employed women.

Effect of an organised screening program on socioeconomic inequalities in mammography practice, knowledge and attitudes

BACKGROUND

Breast cancer stands as the leading cause of cancer related mortality in women worldwide. Mammography screening has the potential to improve prognosis by reducing stage at diagnosis. Socioeconomic inequalities in mammography cancer screening have been widely reported. The influence of organised programs on socioeconomic disparities regarding mammography screening is to date unclear. We aimed to investigate the impact of an organised regional screening program on socioeconomic inequalities in terms of the uptake, knowledge and attitudes towards mammography screening.

METHODS

Data were obtained from two cross-sectional surveys of women 50 to 69 years old conducted in 1998 and 2012, before and after the implementation of an organised breast cancer screening program in Geneva, Switzerland. Socioeconomic status was measured by monthly household income and education level. Logistic and linear regression multivariable models were used to investigate the evolution of socioeconomic gradients between 1998 and 2012 in terms of uptake, knowledge and attitudes towards mammography screening.

RESULTS

In 1998, before the implementation of an organised screening program, 44% of women from the lowest education category reported mammography practice conforming to recommendations versus 63% of the more educated participants. This socioeconomic gradient was no longer present in 2012 where reported mammography practice at guideline-recommended frequency were 83 and 82% in the lowest and highest education level categories respectively (change in education gradient over time, p = 0.018). The difference in mammography practice in agreement with recommendations between the lowest and the highest income category went from 27 percentage points in 1998 to 14 percentage points in 2012 (change in income gradient over time, p = 0.10). The socioeconomic gradient in negative attitudes towards mammography screening persisted in 2012 but was reduced compared to 1998. We did not observe a reduction in the socioeconomic disparities in knowledge regarding mammography screening over this period.

CONCLUSIONS

This study suggests that mammography screening programs may lessen socioeconomic inequities in mammography practice. Such programs should feature adapted communication tools to reach women of lower socioeconomic status to attempt to further reduce socioeconomic gradients in mammography screening.

Is the incidence of advanced-stage breast cancer affected by whether women attend a steady-state screening program?

In this cross-sectional population-based study, we assessed the incidence of advanced breast cancer based on screening attendance. Women from the Netherlands Cancer Registry were included if aged ≥49 years and diagnosed with breast cancer between 2006 and 2011, and data were linked with the screening program. Cancers were defined as screen-related (diagnosed <24 months after screening) or nonscreened (all other breast cancers). Two cut-offs were used to define advanced breast cancer: TNM-stage (III-IV vs 0-I-II) and T-stage alone (≥15 mm vs <15 mm or DCIS). The incidence rates were adjusted for age and logistic regression was used to compare groups. Of the 72,612 included women diagnosed with breast cancer, 44,246 (61%) had screen-related breast cancer. By TNM stage, advanced cancer was almost three times as likely to be at an advanced TNM stage in the nonscreened group compared with the screen-related group (38 and 94 per 100,000, respectively; OR: 2.86, 95%CI: 2.72-3.00). By T-stage, the incidence of advanced cancer was higher overall, and in nonscreened women was significantly higher than in screened women (210 and 169 per 100,000; OR: 1.85, 95%CI: 1.78-1.93). Data on actual screening attendance showed that the incidence of advanced breast cancer was significantly higher in nonscreened women than in screened women, supporting the expectation that screening would cause a stage shift to early detection. Despite critical evaluations of breast cancer screening programs, our data show that breast cancer screening is a valuable tool that can reduce the disease burden in women.

Sex differences in obesity related cancer incidence in relation to type 2 diabetes diagnosis (ZODIAC-49)

Background

Diabetes and obesity seem to be partly overlapping risk factors for the development of obesity-related cancer (mainly breast, prostate and colorectal cancer) in patients with type 2 diabetes (T2DM). In the general population, women have a lower risk for obesity-related cancer compared to men. Previous studies involving cardiovascular disease have shown that T2DM eliminates a female advantage of lower CVD risk in the general population compared to men. It is unclear whether the same could be true for obesity-related cancer. This study aimed to this investigate obesity-related cancer incidence in women and men known with T2DM as compared to the Dutch general population.

Methods

This study included 69,583 patients with T2DM selected from a prospective primary care cohort, which was linked to the Dutch National Cancer Registry to obtain cancer specific data. Obesity-related cancers included liver, kidney, colorectal, gallbladder, pancreas, ovarian, endometrial, advanced prostate cancer, post-menopausal breast cancer and oesophageal adenocarcinoma. Primary outcome was sex-stratified, age and year of cancer diagnosis adjusted standardized incidence ratios (SIRs) for three time periods: 5 years before, the year after diagnosis and the next 4 years after T2DM diagnosis. The Dutch general population was used as reference group.

Results

Women with T2DM were at an increased risk for obesity-related cancer compared to women in the general population already 5 years before diabetes diagnosis (SIR 1.77; 95%CI: 1.63–1.91). In both men and women, there was a peak in obesity-related cancer incidence following diabetes diagnosis (SIR: 1.38; 95%CI 1.11–1.64 and SIR: 2.21; 95%CI 1.94–2.30, respectively). From the second to the fifth year after diabetes diagnosis the obesity-related cancer incidence was higher in women compared to women in the general population (SIR: 2.12; 95%CI 1.94–2.30).

Conclusions

Women with T2DM seem to have a substantially higher obesity-related cancer risk. As opposed to men, in women this risk was already increased years before diabetes diagnosis. These results could imply that a relative advantage of women in the general population with regard to cancer risk is lost in women with T2DM.

Understanding the effects of socioeconomic status along the breast cancer continuum in Australian women: a systematic review of evidence

Background

Globally, the provision of equitable outcomes for women with breast cancer is a priority for governments. However, there is growing evidence that a socioeconomic status (SES) gradient exists in outcomes across the breast cancer continuum – namely incidence, diagnosis, treatment, survival and mortality. This systematic review describes this evidence and, because of the importance of place in defining SES, findings are limited to the Australian experience.

Methods

An on-line search of PubMed and the Web of Science identified 44 studies published since 1995 which examined the influence of SES along the continuum. The critique of studies included the study design, the types and scales of SES variable measured, and the results in terms of direction and significance of the relationships found. To aid in the interpretation of results, the findings were discussed in the context of a systems dynamic feedback diagram.

Results

We found 67 findings which reported 107 relationships between SES within outcomes along the continuum. Results suggest no differences in the participation in screening by SES. Higher incidence was reported in women with higher SES whereas a negative association was reported between SES and diagnosis. Associations with treatment choice were specific to the treatment choice undertaken. Some evidence was found towards greater survival for women with higher SES, however, the evidence for a SES relationship with mortality was less conclusive.

Conclusions

In a universal health system such as that in Australia, evidence of an SES gradient exists, however, the strength and direction of this relationship varies along the continuum. This is a complex relationship and the heterogeneity in study design, the SES indicator selected and its representative scale further complicates our understanding of its influence. More complex multilevel studies are needed to better understand these relationships, the interactions between predictors and to reduce biases introduced by methodological issues.

Geographical differences in risk of advanced breast cancer: Limited evidence for reductions over time, Queensland, Australia 1997-2014

BACKGROUND

Reducing geographical inequalities in breast cancer stage remains a key focus of public health policy. We explored whether patterns of advanced breast cancer by residential accessibility and disadvantage in Queensland, Australia, have changed over time.

METHODS

Population-based cancer registry study of 38,706 women aged at least 30 years diagnosed with a first primary invasive breast cancer of known stage between 1997 and 2014. Multilevel logistic regression was used to examine temporal changes in associations of area-level factors with odds of advanced disease after adjustment for individual-level factors.

RESULTS

Overall 19,401 (50%) women had advanced breast cancer. Women from the most disadvantaged areas had higher adjusted odds (OR = 1.23 [95%CI 1.13, 1.32]) of advanced disease than those from least disadvantaged areas, with no evidence this association had changed over time (interaction p = 0.197). Living in less accessible areas independently increased the adjusted odds (OR = 1.18 [1.09, 1.28]) of advanced disease, with some evidence that the geographical inequality had reduced over time (p = 0.045). Sensitivity analyses for un-staged cases showed that the original associations remained, regardless of assumptions made about the true stage distribution.

CONCLUSIONS

Both geographical and residential socioeconomic inequalities in advanced stage diagnoses persist, potentially reflecting barriers in accessing diagnostic services. Given the role of screening mammography in early detection of breast cancer, the lack of population-based data on private screening limits our ability to determine overall participation rates by residential characteristics. Without such data, the efficacy of strategies to reduce inequalities in breast cancer stage will remain compromised.

The method of detection of ductal carcinoma in situ has no therapeutic implications: results of a population-based cohort study

Background

Population screening with mammography has resulted in increased detection of ductal carcinoma in situ (DCIS). The aim of this population-based cohort study was to assess whether the method of detection should be considered when determining prognosis and treatment in women with DCIS.

Methods

This study includes 7042 women aged 49–75 years, who were surgically treated for primary DCIS between 1989 and 2004 in the Netherlands. We calculated cumulative incidences of ipsilateral and contralateral invasive breast cancer and all-cause mortality among women with screen-detected, interval, or non-screening-related DCIS, and assessed the association between method of detection and these outcomes, using multivariable Cox regression analyses.

Results

Compared with non-screening-related DCIS, women with screen-detected DCIS had a lower risk of developing ipsilateral invasive breast cancer (hazard ratio (HR) = 0.75, 95% CI = 0.59–0.96), but a similar risk of contralateral invasive breast cancer (HR = 0.86, 95% CI = 0.67–1.10). The absolute difference in risk of ipsilateral invasive breast cancer was 1% at 15 years. Screen detection was associated with lower all-cause mortality (HR = 0.85, 95% CI = 0.73–0.98); when we additionally accounted for the occurrence of invasive breast cancer the magnitude of this effect remained similar (HR = 0.86, 95% CI = 0.75–1.00).

Conclusions

Screen detection was associated with lower risk of ipsilateral invasive breast cancer and all-cause mortality. However, the absolute difference in risk of ipsilateral invasive breast cancer was very low and the lower all-cause mortality associated with screen-detected and interval DCIS might be explained by a healthy-user effect. Therefore, our findings do not justify different treatment strategies for women with screen-detected, interval, or non-screening-related DCIS.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-017-0819-4) contains supplementary material, which is available to authorized users.

What might explain deprivation-specific differences in the excess hazard of breast cancer death amongst screen-detected women? Analysis of patients diagnosed in the West Midlands region of England from 1989 to 2011

BACKGROUND

Breast cancer survival is higher in less deprived women, even amongst women whose tumor was screen-detected, but reasons behind this have not been comprehensively investigated.

METHODS

The excess hazard of breast cancer death in 20,265 women diagnosed with breast cancer, followed up to 2012, was estimated for screen-detected and non-screen-detected women, comparing more deprived to less deprived women using flexible parametric models. Models were adjusted for individual and tumor factors, treatment received and comorbidity. For screen-detected women, estimates were also corrected for lead-time and overdiagnosis.

RESULTS

The excess hazard ratio (EHR) of breast cancer death in the most deprived group, adjusted only for age and year of diagnosis, was twice that of the least deprived among screen-detected women (EHR=2.12, 95%CI 1.48-2.76) and 64% higher among non-screen-detected women (EHR=1.64, 95%CI 1.41-1.87). Adjustment for stage at diagnosis lowered these estimates by 25%. Further adjustment had little extra impact. In the final models, the excess hazard for the most deprived women was 54% higher (EHR=1.54, 95%CI 1.10-1.98) among screen-detected women and 39% higher (EHR=1.39, 95%CI 1.20-1.59) among non-screen-detected women.

CONCLUSION

A persistent socio-economic gradient in breast cancer-related death exists in this cohort, even for screen-detected women. The impact of differential lifestyles, management and treatment warrant further investigation.

The relative effect of mammographic screening on breast cancer mortality by socioeconomic status

Breast cancer incidence and mortality are higher in women with a high socioeconomic status (SES). The potential to prevent death from breast cancer is therefore greater in the high SES group. This does, however, require that the effectiveness of screening in the high SES group is equal to or greater than the effectiveness in the low SES group. The aim of this study is to assess the relative effectiveness of mammographic screening on breast cancer mortality by SES.In Nijmegen, the Netherlands, women are invited to participate in biennial mammographic screening since 1975. Postal code is collected at each round and is used to calculate the SES of each woman based on the SES indicator of the Netherlands Institute for Social Research. The Dutch average was used to classify the SES score of each woman as either high or low. We designed a case-control study to investigate the effect of mammographic screening in women aged 50 to 75, 40 to 75, and 50 to 69 years, and calculated the odds ratios (ORs) and 95% confidence intervals (CIs).Among the women invited to the mammographic screening program in Nijmegen, 10% had a high SES. In women aged 50 to 75 years, the breast cancer death rate was 38% lower in screened women than in unscreened women. The ORs for women with high SES (OR 0.82, 95% CI 0.31-2.19) and low SES did not differ significantly (OR 0.61, 95% CI 0.47-0.78).Mammographic screening reduces breast cancer mortality, but we did not observe a significant difference in the relative effectiveness of screening by SES. If the effectiveness of mammographic screening is indeed not dependent on SES status, the absolute number of breast cancer deaths prevented by mammographic screening will be greater in the high SES than low SES group, because women with a high SES have a greater risk of breast cancer death.

Multilevel factors associated with long-term adherence to screening mammography in older women in the U.S

In the U.S., guidelines recommend that women continue mammography screening until at least age 74, but recent evidence suggests declining screening rates in older women. We estimated adherence to screening mammography and multilevel factors associated with adherence in a longitudinal cohort of older women. Women aged 66-75years receiving screening mammography within the Breast Cancer Surveillance Consortium were linked to Medicare claims (2005-2010). Claims data identified baseline adherence, defined as receiving subsequent mammography within approximately 2years, and length of time adherent to guidelines. Characteristics associated with adherence were investigated using logistic and Cox proportional hazards regression models. Analyses were stratified by age to investigate variation in relationships between patient factors and adherence. Among 49,775 women, 89% were adherent at baseline. Among women 66-70years, those with less than a high school education were more likely to be non-adherent at baseline (odds ratio [OR] 1.96; 95% confidence interval [CI] 1.65-2.33) and remain adherent for less time (hazard ratio [HR] 1.41; 95% CI 1.11-1.80) compared to women with a college degree. Women with ≥1 versus no Charlson co-morbidities were more likely to be non-adherent at baseline (OR 1.46; 95% CI 1.31-1.62) and remain adherent for less time (HR 1.44; 95% CI 1.24-1.66). Women aged 71-75 had lower adherence overall, but factors associated with non-adherence were similar. In summary, adherence to guidelines is high among Medicare-enrolled women in the U.S. receiving screening mammography. Efforts are needed to ensure that vulnerable populations attain these same high levels of adherence.

Socioeconomic inequalities in breast cancer incidence and mortality in Europe-a systematic review and meta-analysis

Background: Breast cancer is the leading cause of female cancer in Europe and is estimated to affect more than one in 10 women. Higher socioeconomic status has been linked to higher incidence but lower case fatality, while the impact on mortality is ambiguous. Methods: We performed a systematic literature review and meta-analysis on studies on association between socioeconomic status and breast cancer outcomes in Europe, with a focus on effects of confounding factors. Summary relative risks (SRRs) were calculated. Results: The systematic review included 25 articles of which 8 studied incidence, 10 case fatality and 8 mortality. The meta-analysis showed a significantly increased incidence (SRR 1.25, 1.17–1.32), a significantly decreased case fatality (SRR 0.72, 0.63–0.81) and a significantly increased mortality (SRR 1.16, 1.10–1.23) for women with higher socioeconomic status. The association for incidence became insignificant when reproductive factors were included. Case fatality remained significant after controlling for tumour characteristics, treatment factors, comorbidity and lifestyle factors. Mortality remained significant after controlling for reproductive factors. Conclusion: Women with higher socioeconomic status show significantly higher breast cancer incidence, which may be explained by reproductive factors, mammography screening, hormone replacement therapy and lifestyle factors. Lower case fatality for women with higher socioeconomic status may be partly explained by differences in tumour characteristics, treatment factors, comorbidity and lifestyle factors. Several factors linked to breast cancer risk and outcome, such as lower screening attendance for women with lower socioeconomic status, are suitable targets for policy intervention aimed at reducing socioeconomic-related inequalities in health outcomes.

Comparative effectiveness of two outreach strategies for cervical cancer screening

OBJECTIVE

Test-specific reminder letters can improve cancer screening adherence. Little is known about the effectiveness of a reminder system that targets the whole person by including multiple screening recommendations per letter.

METHODS

We compared the effectiveness of a Pap-specific reminder letter sent 27months after a woman's last Pap, to a reminder letter that included up to seven preventive service recommendations sent before a woman's birthday ("birthday letter") on Pap smear adherence from a natural experiment occurring in routine clinical care. Participants included 82,016 women from Washington State who received 72,615 Pap-specific letters between 2003 and 2007 and 100,218 birthday letters between 2009 and 2012. We defined adherence as having a Pap test within a six month window around the Pap test due date. Using logistic regression, we calculated adjusted odds ratios (OR) for adherence with 95% confidence intervals (CI) following the birthday letter with 1-2 recommendations, 3-5 recommendations, and 6-7 recommendations compared to the Pap-specific letter. All analyses were stratified by whether a woman was up-to-date or overdue for screening at the time she received a letter.

RESULTS

Adjusted ORs showed reduced adherence following the birthday letter compared with the Pap-specific letter for up-to-date women whether the letter had 1-2 recommendations (OR=0.37, 95%CI=0.36-0.39), 3-5 recommendations (OR=0.44, 95%CI=0.42-0.45), or 6-7 recommendations (OR=0.36, 95%CI=0.32-0.40). We noted no difference in Pap-test adherence between letter types for overdue women.

CONCLUSIONS

In conclusion, for women regularly adherent to screening, an annual birthday letter containing reminders for multiple preventive services was less effective at promoting cervical cancer screening compared with a Pap-specific letter.

Risk of second primary malignancies among 1537 melanoma patients and risk of second primary melanoma among 52 354 cancer patients in Northern Italy

BACKGROUND

The number of melanoma survivors has been increasing for decades due to early diagnosis and improved survival. These patients have an increased risk of developing a second primary cancer (SPC); also, melanoma is frequently diagnosed among patients firstly diagnosed with an extracutaneous malignancy.

OBJECTIVE

We evaluated the risk of developing a SPC among 1537 melanoma patients, and the risk of second primary melanoma (SPM) in 52 354 extracutaneous cancer patients, who were treated at the European Institute of Oncology in Milan, Italy, during 2000-2010.

MATERIAL AND METHODS

We calculated standardized incidence ratios (SIR) by applying gender-, age-, year- and region-specific reference rates to the follow-up time accrued between the diagnosis of the first and the second primary malignancies.

RESULTS

Seventy-six SPC were diagnosed during a median follow-up of 4 years, of which 49 (64%) during the first 2 years upon melanoma diagnosis. The SIR was increased for cancer of breast (4.10, 95% CI 2.79-6.03), thyroid (4.67, 95% CI 1.94-11.22), brain (6.13, 95% CI 2.30-16.33) and for non-Hodgkin lymphoma (3.12, 95% CI 1.30-7.50). During a median follow-up of 4 years, 127 SPM were diagnosed: thick lesions were less frequent than for melanoma diagnosed as first cancer. The SIR was increased for cancer of breast (5.13, 95%CI 3.91-6.73), thyroid (16.2, 95%CI: 5.22-50.2), head and neck (5.62, 95%CI 1.41-22.50), soft tissue (8.68, 95%CI 2.17-34.70), cervix (12.5, 95% CI 3.14-50.20), kidney (3.19, 95%CI 1.52-6.68), prostate (4.36, 95%CI 2.63-7.24) and acute myeloid leukaemia (6.44, 95%CI 2.42-17.20).

CONCLUSIONS

The most likely causes of these associations are the clustering of lifestyle risk factors in the same subgroups of population, mainly on a sociocultural basis and surveillance bias. This raises important questions about how to best follow cancer survivors by avoiding an inefficient use of resources and an excessive medicalization of these patients' lives.

Explaining the Better Prognosis of Screening-Exposed Breast Cancers: Influence of Tumor Characteristics and Treatment

BACKGROUND

In England, population mammographic screening has been offered to women for over 20 years. Overall decrease in breast cancer mortality rates and improvements in cancer awareness and organization of medical care over this period call for a more current evaluation of the mediators behind the better prognosis of screening-exposed breast cancers.

METHODS

A case-control study was conducted within the English National Breast Screening Program. Women who died from primary breast cancer in 2008 to 2009 were matched (by year of birth, screening invitation, and area) to controls that received a diagnosis of invasive breast cancer at the time of the case diagnosis but survived the case death. Data were analyzed by unconditional logistic regression with adjustment for matching factors.

RESULTS

The unadjusted OR for dying from breast cancer associated with ever having attended breast screening was 0.44 [95% confidence interval (CI), 0.33-0.58]. After adjustment for lead time, overdiagnosis, and self-selection, the OR increased to 0.69 (95% CI, 0.50-0.94). Adjusting for tumor size, lymph node status, stage, grade, histopathology, and laterality accounted for all the screening effect (OR, 1.00; 95% CI, 0.71-1.40). Further adjustment for treatment factors only had a minimal impact on the OR (OR, 1.02; 95% CI, 0.72-1.45).

CONCLUSIONS

Our results suggest that earlier diagnosis, as reflected by tumor characteristics, remains the major mediator of the improvement in breast cancer survival due to participation in mammographic screening.

IMPACT

Mammographic screening continues to prevent breast cancer-related deaths in the epoch of adjuvant systemic therapy.

Does the Neighborhood Area of Residence Influence Non-Attendance in an Urban Mammography Screening Program? A Multilevel Study in a Swedish City

BACKGROUND AND AIM

The public health impact of population-based mammography screening programs depends on high participation rates. Thus, monitoring participation rates, as well as understanding and considering the factors influencing attendance, is important. With the goal to acquire information on the appropriate level of intervention for increasing screening participation our study aimed to (1) examine whether, over and above individual factors, the neighborhood of residence influences a woman's mammography non-attendance, and (2) evaluate, whether knowing a woman's neighborhood of residence would be sufficient to predict non-attendance.

METHODS

We analyze all women invited to mammography screening in 2005-09, residing in the city of Malmö, Sweden. Information regarding mammography screening attendance was linked to data on area of residence, demographic and socioeconomic characteristics available from Statistics Sweden. The influence of individual and neighborhood factors was assessed by multilevel logistic regression analysis with 29,901 women nested within 212 neighborhoods.

RESULTS

The prevalence of non-attendance among women was 18.3%. After adjusting for individual characteristics, the prevalence in the 212 neighborhoods was 3.6%. Neighborhood of residence had little influence on non-attendance. The multilevel analysis indicates that 8.4% of the total individual differences in the propensity of non-attendance were at the neighborhood level. However, when adjusting for specific individual characteristics this general contextual effect decreased to 1.8%. This minor effect was explained by the sociodemographic characteristic of the neighborhoods. The discriminatory accuracy of classifying women according to their non-attendance was 0.747 when considering only individual level variables, and 0.760 after including neighborhood level as a random effect.

CONCLUSION

Our results suggest that neighborhoods of residence in Malmö, Sweden (as defined by small-area market statistics (SAMS) areas) do not condition women's participation in population based mammography screening. Thus, interventions should be directed to the whole city and target women with a higher risk of non-attendance.

Non-attendance in mammography screening and women's social network: a cohort study on the influence of family composition, social support, attitudes and cancer in close relations

Background

Mammography screening can reduce breast cancer mortality. The aim of the present study was to investigate non-attendance in mammography screening in relation to different aspects of a women’s social network, attitudes and cancer in close relations.

Methods

Data from the Malmö Diet and Cancer Study baseline examination in 1991–1996 was used. A re-examination began in 2007, and 1452 women participated. Family composition, social support, sense of belonging, attitudes on screening and breast cancer risk and on previous cancer in close relations were investigated in relation to self-reported participation in mammography screening using logistic regression analysis, yielding odds ratios with 95 % confidence intervals.

Results

Both attendees (98.0 %) and non-attendees (95.2 %) considered mammography screening important. Non-attendance in mammography screening was associated with being unmarried vs. married (2.40:1.30–4.45) and with not having vs. having children (1.77:1.08–2.92). Non-attendees planned to abstain from mammography screening in the future more often than attendees (4.78:2.56–8.90), and they had often abstained from cervical cancer screening (1.69:1.04–2.75). No other statistically significant association was found.

Conclusions

This study indicates that family composition, but not necessarily the presence or absence of social support, perceived cancer risk or cancer in close relations, may affect non-attendance in mammography screening. A positive attitude towards mammography screening was found among both attendees and non-attendees, although the latter group planned to a lesser degree to attend mammography screening in the future.

Impact of mammographic screening on ethnic and socioeconomic inequities in breast cancer stage at diagnosis and survival in New Zealand: a cohort study

Background

Indigenous Māori women experience a 60% higher breast cancer mortality rate compared with European women in New Zealand. We explored the impact of differences in rates of screen detected breast cancer on inequities in cancer stage at diagnosis and survival between Māori and NZ European women.

Methods

All primary breast cancers diagnosed in screening age women (as defined by the New Zealand National Breast Cancer Screening Programme) during 1999–2012 in the Waikato area (n = 1846) were identified from the Waikato Breast Cancer Register and the National Screening Database. Stage at diagnosis and survival were compared for screen detected (n = 1106) and non-screen detected (n = 740) breast cancer by ethnicity and socioeconomic status.

Results

Indigenous Māori women were significantly more likely to be diagnosed with more advanced cancer compared with NZ European women (OR = 1.51), and approximately a half of this difference was explained by lower rate of screen detected cancer for Māori women. For non-screen detected cancer, Māori had significantly lower 10-year breast cancer survival compared with NZ European (46.5% vs. 73.2%) as did most deprived compared with most affluent socioeconomic quintiles (64.8% vs. 81.1%). No significant survival differences were observed for screen detected cancer by ethnicity or socioeconomic deprivation.

Conclusions

The lower rate of screen detected breast cancer appears to be a key contributor towards the higher rate of advanced cancer at diagnosis and lower breast cancer survival for Māori compared with NZ European women. Among women with screen-detected breast cancer, Māori women do just as well as NZ European women, demonstrating the success of breast screening for Māori women who are able to access screening. Increasing breast cancer screening rates has the potential to improve survival for Māori women and reduce breast cancer survival inequity between Māori and NZ European women.

Socioeconomic disparity in survival after breast cancer in ireland: observational study

We evaluated the relationship between breast cancer survival and deprivation using data from the Irish National Cancer Registry. Cause-specific survival was compared between five area-based socioeconomic deprivation strata using Cox regression. Patient and tumour characteristics and treatment were compared using modified Poisson regression with robust variance estimation. Based on 21356 patients diagnosed 1999-2008, age-standardized five-year survival averaged 80% in the least deprived and 75% in the most deprived stratum. Age-adjusted mortality risk was 33% higher in the most deprived group (hazard ratio 1.33, 95% CI 1.21-1.45, P<0.001). The most deprived groups were more likely to present with advanced stage, high grade or hormone receptor-negative cancer, symptomatically, or with significant comorbidity, and to be smokers or unmarried, and less likely to have breast-conserving surgery. Cox modelling suggested that the available data on patient, tumour and treatment factors could account for only about half of the survival disparity (adjusted hazard ratio 1.18, 95% CI 0.97-1.43, P = 0.093). Survival disparity did not diminish over time, compared with the period 1994-1998. Persistent survival disparities among Irish breast cancer patients suggest unequal use of or access to services and highlight the need for further research to understand and remove the behavioural or other barriers involved.

Effect of implementation of the mass breast cancer screening programme in older women in the Netherlands: population based study

OBJECTIVE

To assess the incidence of early stage and advanced stage breast cancer before and after the implementation of mass screening in women aged 70-75 years in the Netherlands in 1998.

DESIGN

Prospective nationwide population based study.

SETTING

National cancer registry, the Netherlands.

PARTICIPANTS

Patients aged 70-75 years with a diagnosis of invasive or ductal carcinoma in situ breast cancer between 1995 and 2011 (n=25,414). Incidence rates were calculated using population data from Statistics Netherlands.

MAIN OUTCOME MEASURE

Incidence rates of early stage (I, II, or ductal carcinoma in situ) and advanced stage (III and IV) breast cancer before and after implementation of screening. Hypotheses were formulated before data collection.

RESULTS

The incidence of early stage tumours significantly increased after the extension for implementation of screening (248.7 cases per 100,000 women before screening up to 362.9 cases per 100,000 women after implementation of screening, incidence rate ratio 1.46, 95% confidence interval 1.40 to 1.52, P<0.001). However, the incidence of advanced stage breast cancers decreased to a far lesser extent (58.6 cases per 100,000 women before screening to 51.8 cases per 100,000 women after implementation of screening, incidence rate ratio 0.88, 0.81 to 0.97, P<0.001).

CONCLUSIONS

The extension of the upper age limit to 75 years has only led to a small decrease in incidence of advanced stage breast cancer, while that of early stage tumours has strongly increased.

The risk of developing a second primary cancer in melanoma patients: a comprehensive review of the literature and meta-analysis

The number of cutaneous melanoma survivors has been increasing for years due to improvements in early diagnosis and subsequent prolonged survival. These patients are at increased risk of developing a second melanoma and a second primary malignancy (SPM) at other sites as well. We performed a review of scientific literature and meta-analysis to evaluate the risk of developing a SPM (other than melanoma) among melanoma patients. Twenty-three independent papers and over 350,000 melanoma patients were included. Risk of cancer among melanoma survivors was increased overall (1.57, 95% CI 1.29-1.90) and at several sites: bone (2.09, 95% CI 1.08-4.05), non-melanoma skin cancer (4.01, 95% CI 1.81-8.87), soft tissue (6.80, 95% CI 1.29-35.98), colon-rectum (1.12, 95% CI 1.00-1.25), female breast (1.14, 95% CI 1.07-1.22), kidney (1.34, 95% CI 1.23-1.45), prostate (1.25, 95% CI 1.13-1.37) and non-Hodgkin lymphoma (1.37, 95% CI 1.22-1.54). The overall risk of SPM showed a tendency to decrease as the time from melanoma diagnosis lengthened. Most of our findings may be explained by the tendency of some exposures, which are risk factors for different tumors, to occur simultaneously in the same individuals. These results suggest primary and secondary cancer prevention counselling for melanoma survivors.

The impact of comorbidity on cancer survival: a review

Background

A number of studies have shown poorer survival among cancer patients with comorbidity. Several mechanisms may underlie this finding. In this review we summarize the current literature on the association between patient comorbidity and cancer prognosis. Prognostic factors examined include tumor biology, diagnosis, treatment, clinical quality, and adherence.

Methods

All English-language articles published during 2002–2012 on the association between comorbidity and survival among patients with colon cancer, breast cancer, and lung cancer were identified from PubMed, MEDLINE and Embase. Titles and abstracts were reviewed to identify eligible studies and their main results were then extracted.

Results

Our search yielded more than 2,500 articles related to comorbidity and cancer, but few investigated the prognostic impact of comorbidity as a primary aim. Most studies found that cancer patients with comorbidity had poorer survival than those without comorbidity, with 5-year mortality hazard ratios ranging from 1.1 to 5.8. Few studies examined the influence of specific chronic conditions. In general, comorbidity does not appear to be associated with more aggressive types of cancer or other differences in tumor biology. Presence of specific severe comorbidities or psychiatric disorders were found to be associated with delayed cancer diagnosis in some studies, while chronic diseases requiring regular medical visits were associated with earlier cancer detection in others. Another finding was that patients with comorbidity do not receive standard cancer treatments such as surgery, chemotherapy, and radiation therapy as often as patients without comorbidity, and their chance of completing a course of cancer treatment is lower. Postoperative complications and mortality are higher in patients with comorbidity. It is unclear from the literature whether the apparent undertreatment reflects appropriate consideration of greater toxicity risk, poorer clinical quality, patient preferences, or poor adherence among patients with comorbidity.

Conclusion

Despite increasing recognition of the importance of comorbid illnesses among cancer patients, major challenges remain. Both treatment effectiveness and compliance appear compromised among cancer patients with comorbidity. Data on clinical quality is limited.